Cause: DC link voltage undervoltage comes when the voltage in the DC link of the drive has fallen below a permissible threshold. The incoming AC mains voltage might be too low or experiencing significant dips.

f30003 DC link voltage undervoltage fault in siemens drive indicates that the internal DC bus voltage in the drive has dropped below its minimum limit, which can damage the drive or cause unstable operation, so it shuts down.

Troubleshooting Steps:

• Use a multimeter to check the voltage at the drive's input terminals and ensure it's within the specified range for the drive.
• Check the line supply phases.
• Double-check that the drive is connected to the correct mains voltage as indicated on its nameplate.
• Check drive rectifier using multimeter.